Effect of siaD on Ag-8 to improve resistance to crown gall in grapes and related mechanisms.

Crown gall caused by Agrobacterium vitis (A. vitis) is one of the crucial issues restricting the to grape industry. In this study, Agrobacterium tumefaciens (Ag-8) was separated from the soil that could prevent the occurrence of grape crown gall. By the mutagenesis of Ag-8 transposon, the siaD gene deletion strain (ΔsiaD) showed significantly lower efficacy in grape and tomato plants for controlling grape crown gall, but the relevant mechanism was not clear. The biofilm formation and motility of ΔsiaD were significantly decreased, and the colonization ability of ΔsiaD in tomato roots was significantly reduced. RNA-seq analysis showed that the expression of nemR significantly reduced in the ΔsiaD and that the expression of nemR showed a high correlation with biofilm and motility. Further studies showed that the nemR gene deletion strain of Ag-8 (ΔnemR) showed significantly reduced motility, biofilm formation and control of grape crown gall compared to Ag-8, and the nemR gene complementary strain of Ag-8 (ΔnemR-comp) recovered to Ag-8 wild-type levels. The inoculation experiments of preventive, curative or simultaneous treatment further showed that the preferential inoculation with Ag-8 reduced the incidence of grape crown gall on tomato plants, and studies showed that the mutation of siaD affected the site competition between Ag-8 and A. vitis, and that the mutation of nemR was consistent with the previous results. This study provides a new strategy for the prevention and control of grape crown gall, which is of great significance to the grape industry to increase production and income.

Braces versus casts for post-operational immobilization of ankle fractures: A meta-analysis.

Background and aims: Both casts and braces can be used for post-operational immobilization of ankle fractures. This meta-analysis aimed to assess the complications and functional effects of the two types of immobilization. Material and methods: PubMed, Embase, Cochrane, and CNKI was searched for randomized controlled trials (published between Jan 1, 1950, and March 2022). Relative risk (RR) or standard mean difference (SMD) with a 95% confidence interval (CI) was used to present the outcomes. The pooled data were assessed by using the fixed-effects model or random-effects model. Results: A total of 5 randomized controlled studies involving 930 subjects were included according to our inclusion criteria. On the ankle score at 6w,12w and 52w, there was no statistically significant difference between the two groups. In terms of 6w, the brace group showed better ankle dorsiflexion (MD = 6.78, 95% CI 0.56-13.00, p = 0.03) and plantar flexion (MD = 6.58, 95% CI 1.60-11.55, p = 0.01) than the cast group. The wound complications (RR = 3.49, 95% CI 1.32 to 9.24, p = 0.01) and total complications (RR = 3.54, 95% CI 1.92 to 6.50, p < 0.0001) in the brace group were three times more than that in the cast group. There was no statistically significant difference between the two groups in the non-wound complications. There was no statistically significant difference between the two groups in the time of going back to work, swelling of the ankle, and atrophy of the calf muscle. Conclusion: The short-term and long-term functional outcomes after postoperative treatment of adult ankle fractures with braces are similar to those with casts. The usage of braces may cause three times more wound complications than that of casts.

Preparation and properties of a novel biodegradable polyester elastomer with functional groups.

A novel biodegradable poly(sebacate-glycerol-citrate) (PGSC) elastomer with functional groups was prepared in this study. First, moldable mixtures were obtained by mixing citric acid with the poly(glycerol-sebacate) (PGS) pre-polymers synthesized in our lab. The PGSC elastomers were obtained from moldable mixtures that were thermally cured in the moulds. Then, the structures, compositions and properties of the elastomers were studied by Fourier transformation infrared spectroscopy (FT-IR), swelling test, differential scanning calorimeter (DSC), tensile test, water contact angle measurement, water absorption experiments and a in vitro degradation test. It showed that the hydroxyl groups remained in the elastomers which would endow the polymer chains with functionality such as good surface modification. By controlling the thermal curing time, the compositions of the PGSC elastomers were adjusted for different mechanical and biodegradable properties. Therefore, PGSC elastomers might be used as anti-conglutination films in surgery, guided tissue regeneration membranes and drug-delivery matrices.

Recent advances in synthetic bioelastomers.

This article reviews the degradability of chemically synthesized bioelastomers, mainly designed for soft tissue repair. These bioelastomers involve biodegradable polyurethanes, polyphosphazenes, linear and crosslinked poly(ether/ester)s, poly(epsilon-caprolactone) copolymers, poly(1,3-trimethylene carbonate) and their copolymers, poly(polyol sebacate)s, poly(diol-citrates) and poly(ester amide)s. The in vitro and in vivo degradation mechanisms and impact factors influencing degradation behaviors are discussed. In addition, the molecular designs, synthesis methods, structure properties, mechanical properties, biocompatibility and potential applications of these bioelastomers were also presented.